Helium_123

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Helium,He,2 Helium Atomic Weight: 4.00260 Helium Discovery: Janssen, 1868, some sources say Sir William Ramsey, Nils Langet, P.T. Cleve 1895 Uses: Helium is widely used in cryogenic research because its boiling point is near absolute zero. It is used in the study of superconductivity, as an inert gas shield for arc welding, as a protective gas in growing silicon and germanium crystals and producing titanium and zirconium, for pressuring liquid fuel rockets, for use in magnetic resonance imaging (MRI), as a cooling medium for nuclear reactors, and as a gas for supersonic wind tunnels. A mixture of helium and oxygen is used as an artificial atmosphere for divers and others working under pressure. Helium is used for filling balloons and blimps.

Common use Main filling for blimps (airships) Used to fill balloons Detects leaks in sealed containers Gas shield for arc welding Growing silicon and germanium crystals for protective shields Production of protective shields using titanium and zirconium As a cooling factor in nuclear reactors Artificial atmosphere created with 20% oxygen Cryogenic applications (low temperature) Pressurizing liquid fuel rockets


 * This is Helium Neon laser.**